Issue
Context
I'm currently working on yocto on a build for raspberrypi 4 (not really relevant). I would like to create two recipes for two different images:
- An image with the bare minimum to run fast. Mostly for production phase
- An image with a lot of extra tools and debug options
Basically the core idea is pretty easy to sort out, I just create two image files, the first one requires the basic recipes for my image, the second one requires the first file and requires a few additional modules (such as apt, valgrind, gdb, etc...).
Question
Now here is the issue: Most of my recipes are built with cmake. I would like to add extra flags (especially -g) when building for the debug image.
What is the best way or most common way to do that? Is there a good practice?
To me this is a little tricky due to the fact that bitbake does not supports the if statement.
My solution
For now here is the solution I found: In the image recipe for the dev file add a variable to define the debug mode:
DEBUG_MODE = "1"
Then in every file that compiles a module with cmake conditionally add the flag (-g for example):
TARGET_CXXFLAGS += "${@'-g' if d.getVar('DEBUG_MODE') == '1' else ''}"
However I'm not sure how this apply to dependencies, and I'm not sure if it is the best way to do it. It seems like a lot of duplicate code and tedious to maintain. Is there anything easier to manage?
Solution
Currently you set
DEBUG_MODE = "1"
but then check for DEV_MODE in your if condition, so this approach should not work at all.
Suggestion: Set -g globally
One step could be to define TARGET_CPPFLAGS in a *.conf for your debug-image to include -g.
TARGET_CPPFLAGS += "-g"
That way there should be no need to add it on recipe base, but can be done globally. Also when it is added in a conf only used for your debug image, there is no need for any if/else.
I would also use TARGET_CPPFLAGS, as those are then used for c and c++. But bear in min that some recipes might unset the compiler flags again.
Answered By - Sunme